Insect alarm pheromones are chemical substances that are synthesized and released in response to predators to reduce predation risk. Alarm pheromones can also be perceived by predators, who take advantage of alarm cues to locate prey. While selection favors evolution of alarm pheromone signals that are not easily detectable by predators, predator evolution selects for better prey detection ability. Here, we review the diversity of alarm signals, and consider the behavioral and ecological conditions under which they have evolved. We show that components of alarm pheromones are similar across many insects, although aphids exhibit different behavioral responses to alarm cues compared to social insects. The effects of alarm pheromones on prey behavior depend on factors such as the concentration of pheromones and the density of conspecifics. We also discuss the molecular mechanisms of alarm pheromone perception underlying the evolutionary arms race between predators and prey, and the function of olfactory proteins and receptors in particular. Our review provides a novel synthesis of the diversity and function of insect alarm pheromones, while suggesting avenues that might better allow researchers to exploit population-level responses to alarm signaling for the sustainable management of pests and vector-borne pathogens.

昆虫警报信息素是为应对捕食者而合成和释放以降低捕食风险的化学物质。捕食者也可以感知警报信息素，他们利用警报线索来定位猎物。虽然选择有利于捕食者不易检测到的警报信息素信号的进化，但捕食者进化选择更好的猎物检测能力。在这里，我们回顾了警报信号的多样性，并考虑了它们进化的行为和生态条件。我们表明警报信息素的成分在许多昆虫中是相似的，尽管与社会昆虫相比，蚜虫对警报线索表现出不同的行为反应。警报信息素对猎物行为的影响取决于信息素浓度和同种密度等因素。我们还讨论了捕食者和猎物之间进化军备竞赛的警报信息素感知的分子机制，特别是嗅觉蛋白和受体的功能。我们的综述提供了昆虫警报信息素的多样性和功能的新综合，同时提出了可能更好地让研究人员利用种群水平对警报信号的反应以可持续管理害虫和媒介传播病原体的途径。